Osteogenic fusion device

Abstract

An interbody osteogenic fusion device is provided that includes a rigid elongated central element and a pair of opposing bone engaging members. The device promotes fusion bone growth in the space between adjacent vertebrae. In one aspect, a cylindrical end cap is coupled to one end of the central element. The opposing bone engaging members are configured to contact and support the adjacent vertebrae. The opposing bone engaging members are coupled at opposite sides of the central element and extend from the end cap to the other end of the central element. The central element, cylindrical end cap, and bone engaging members define opposite cavities for containing osteogenic material.

What is claimed is:  
     
         1 . An implant for promoting fusion bone growth in a space between upper and lower adjacent vertebrae, comprising: 
 a rigid elongated central element having a first end, a second end, and opposite sides;    a pair of opposing bone engaging members configured to contact and support the upper and lower adjacent vertebrae, said opposing bone engaging members being coupled at said opposite sides of said central element; and    wherein said opposing bone engaging members and said central element define opposite cavities for containing osteogenic material.    
     
     
         2 . The implant of    claim 1   , wherein said bone engaging members are tapered to conform to the space between the adjacent vertebrae.  
     
     
         3 . The implant of    claim 1   , wherein said central element has at least one aperture extending between said opposite cavities.  
     
     
         4 . The implant of    claim 1   , wherein said opposing bone engaging members are threaded.  
     
     
         5 . The implant of    claim 1   , wherein said opposing bone engaging members have apertures formed therein.  
     
     
         6 . The implant of    claim 1   , wherein said central element bisects said opposing bone engaging members.  
     
     
         7 . The implant of    claim 1   , wherein said central element and said opposing bone engaging members are integrally formed together.  
     
     
         8 . The implant of    claim 1   , wherein said central element has a pair of slots provided therein.  
     
     
         9 . The implant of    claim 1   , further comprising the osteogenic material provided in said cavities.  
     
     
         10 . The implant of    claim 1   , wherein said central element has a rectangular shape.  
     
     
         11 . The implant of    claim 1   , wherein said central element is solid.  
     
     
         12 . An implant for promoting fusion between an upper and lower vertebra, comprising: 
 an upper bone engaging shell for engaging the upper vertebra;    a lower bone engaging shell for engaging the lower vertebra;    a center beam spacing said upper bone engaging shell and said lower bone engaging shell.    
     
     
         13 . The implant of    claim 12   , wherein said upper bone engaging shell has a longitudinal axis and said central beam extends substantially along said longitudinal axis.  
     
     
         14 . The implant of    claim 12   , wherein said upper shell has a first width, said lower shell has a second width, and said central beam has a third width, said third width less than said first and second widths such that said upper and lower shells over hang said central beam.  
     
     
         15 . The implant of    claim 12   , wherein said central beam includes a first end, an opposite second end and a middle portion, said upper and lower shells extending adjacent at least said first end and said opposite end.  
     
     
         16 . The implant of    claim 15   , wherein said upper and lower shells extend along said central beam from adjacent said first end to adjacent said second end.  
     
     
         17 . The implant of    claim 12   , further including a thread pattern defined on said upper bone engaging shell and said lower bone engaging shell.  
     
     
         18 . An implant for promoting fusion between adjacent vertebrae, comprising: 
 a body having an upper bone engaging surface and a lower bone engaging surface spaced by an intermediate member said body having a longitudinal axis and said intermediate member extending along said longitudinal axis, said upper bone engaging surface and said lower bone engaging surface defining an internal cavity, said cavity interrupted by said intermediate member.    
     
     
         19 . The implant of    claim 18   , wherein said upper and lower bone engaging surfaces have a first width and said intermediate member has a second width, said second width less than one half said first width.  
     
     
         20 . The implant of    claim 18   , wherein said body is integral.  
     
     
         21 . The implant of    claim 8   , wherein said upper bone engaging surface and said lower bone engaging surface are arc segments.  
     
     
         22 . The implant of    claim 21   , wherein said arc segments extend along the length of said intermediate member.  
     
     
         23 . The implant of    claim 22   , further including a cylindrical end cap positioned on one end of said intermediate member.  
     
     
         24 . An interbody spacer for positioning between upper and lower vertebrae, comprising: 
 a body formed into a substantial I-beam configuration with an upper bone engaging surface adapted for engagement with the upper vertebra and a lower bone engaging surface adapted for engagement with the lower vertebra and a central wall extending between and substantially perpendicular to said bone engaging surfaces.